Polysulfonate Sennoside A &amp; B compounds and method of use

ABSTRACT

Polysulfonated Sennoside A and B derivatives, useful as complement inhibitors and the process of making such compounds.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates to novel polysulfonated Sennoside A and B derivatives and to their use as inhibitors of the complement system of warm-blooded animals. The invention further concerns a process for making such compounds.

2. Description of the Prior Art

The term "complement" refers to a complex group of proteins in body fluids that, working together with antibodies or other factors, play an important role as mediators of immune, allergic, immunochemical and/or immunopathogical reactions. The reactions in which complement participates take place in blood serum or in other body fluids, and hence are considered to be humoral reactions.

With regard to human blood, there are at present more than 20 proteins in the complement system consisting of the so-called classical and alternative pathways. These complement proteins are generally designated by the letter C and by number: C1, C2, C3 and so on up to C9. The complement protein C1 is actually an assembly of subunits designated C1q, C1r and C1s. The numbers assigned to the complement proteins reflect the sequence in which they become active, with the exception of complement protein C4, which reacts after C1 and before C2. The numerical assignments for the proteins in the complement system were made before the reaction sequence was fully understood. A more detailed discussion of the complement system and its biochemical, biological and pathological role in the body processes can be found in, for example, Bull. W.H.O. 39: 935 (1968); Annu. Rev. Med. 19: 1 (1968); John Hopkins Med. J. 128: 57 (1971); Harvey Lect. 66: 75 (1972); N. Engl. J. Med. 287: 452, 489, 454, 592, 642 (1972); Sci. Am. 229 (5): 54 (1973); Fed. Proc. 32: 134 (1973): Med. World, Oct. 11, 1974, p. 53; J. Allergy Clin. Immunol. 53: 298 (1974); Cold spring Harbo Conf. Cell Proliferation 2/Proteases Biol. Control: 229 (1975); Annu. Rev. Biochem. 44: 697 (1975); Complement in Clinical Medicine, Dis. Mon. (1975); Complement, Scope, December 1975; Ann. Intern. Med. 84: 580 (1976); Transplant Rev.: 32 (1976); "Complement: Mechanisms and Functions", Prentice-Hall, Englewood Cliffs, N.J. (1976); Essays Med. Biochem. 2: 1 (1976); Hosp. Pract. 12: 33 (1977); Perturbation of Complement in Disease, Chap. 15 in Biol. Amplification Systems in Immunol. (Ed. Day and Good), Plenum, New York and London (1977); Am. J. Clin. Pathol. 68: 647 (1977); Biochem. Soc. Trans. 5: 1659 (1977); Harvey Lect. 72: 139 (1976-1977); J. Periodontal. 48: 505 (1977); Biochem. Soc. Trans. 6: 798 (1978); Clin. and Exp. Dermatol. 4: 271 (1979); Infect, Dis. Rev. 1: 483 (1979).

The complement system (e.g., classical pathway) can be considered to consist of three subsystems: (1) a recognition unit (C1q) which enables it to combine with antibody molecules that have detected a foreign invader; (2) an activation unit (C1r, C1s, C2, C4, C3) which prepares a site on the neighboring membrane; and (3) an attack unit (C5, C6, C7, C8 and C9) which creates a "hole" in the membrane. The membrane attack unit is nonspecific; it destroys invaders only because it is generated in their neighborhood. In order to minimize damage to the host's own cells, its activity must be limited in time. This limitation is accomplished partly by the spontaneous decay of activated complement and partly by interference by inhibitors and destructive enzymes. The control of complement, however, is not perfect, and there are times when damage is done to host's cells. Immunity is, therefore, a double-edged sword.

Activation of the complement system also accelerates blood clotting. This action comes about by way of the complement-mediated release of a clotting factor from platelets. The biologically active complement fragments and complexes become involved in reactions that damage the host's cells. These pathogenic reactions can result in the development of immune-complex diseases. For example, in some forms of nephritis, complement damages the basal membrane of the kidney, resulting in the escape of protein from the blood into the urine. The disease disseminated lupus erythematosus belongs in this category; its symptoms include nephritis, visceral lesions and skin eruptions. The treatment of diphtheria or tetanus with the injection of large amounts of antitoxin sometimes results in serum sickness, an immune-complex disease. Rheumatoid arthritis also involves immune complexes. Like disseminated lupus erythematosus, it is an autoimmune disease in which the disease symptoms are caused by pathogical effects of the immune system in the host's tissues. In summary, the complement system has been shown to be involved with inflammation, coagulation fibrinolysis, antibody-antigen reactions and other metabolic processes.

In the presence of antibody-antigen complexes the complement proteins are involved in a series of reactions which may lead to irreversible membrane damage if they occur in the vicinity of biological membranes. Thus, while complement constitutes a part of the body's defense mechanism against infection, it also results in inflammation and tissue damage in the immunopathological process. The nature of certain complement proteins, suggestion regarding the mode of complement binding to biological membranes and the manner in which complement effects membrane damage are discussed in Annu. Rev. Biochem. 38: 389 (1969); J. Exp. Med. 141: 724 (1975); J. Immunol. 116: 1431 (1976); 119: 1, 1195, 1358, 1482 (1977); 120: 1841 (1978); Immunochemistry 15: 813 (1978); J. Biol. Chem. 254: 9908 (1979).

A variety of substances have been disclosed as inhibiting the complement system, i.e., as complement inhibitors. For example, the compounds 3,3'-ureylenebis[6-(2-amino-8-hydroxy-6-sulfo-1-naphthylazo)benzenesulfonic acid], tetrasodium salt (chlorazol fast pink), heparin and a sulphated dextran have been reported to have an anticomplementary effect, Br. J. Exp. Pathol. 33: 327 (1952). German Pat. No. 2,254,893 or South African Pat. No. 727,923 discloses certain 1-(diphenylmethyl)-4-(3-phenylallyl)piperazines useful as complement inhibitors. Other chemical compounds having complement inhibiting activity are disclosed in, for example, J. Med. Chem. 12: 415, 902, 1049, 1053 (1969); Can. J. Biochem. 47: 547 (1969); J. Immunol. 104: 279 (1970); J. Immunol. 106: 241 (1971); J. Immunol. 111: 1061 (1973); Biochim. Biophys. Acta 317: 539 (1973); Life Sci. 13: 351 (1973); J. Immunol. 113: 584 (1974); Immunology 26: 819 (1974); J. Med. Chem. 17: 1160 (1974); Biochim. Biophys. Res. Comm. 67: 225 (1975); Ann. N.Y. Acad. Sci. 256: 441 (1975); J. Med. Chem. 19: 634, 1079 (1976); J. Immunol. 118: 466 (1977); Arch. Int. Pharmacodyn. 226: 281 (1977); Biochem. Pharmacol. 26: 325 (1977); J. Pharm. Sci. 66: 1367 (1977); Chem. Pharm. Bull. 25: 1202 (1977); Biochim. Biophys. Acta 484: 417 (1977); J. Clin. Microbiol. 5: 278 (1977); Immunochemistry 15: 231 (1978); Immunology 34: 509 (1978); J. Exp. Med. 147: 409 (1978); Thromb. Res. 14: 179 (1979); J. Immunol. 122: 2418 (1979); J. Chem. Soc. Chem. Comm. 726 (1979); Immunology 36: 131 (1979); Biochim. Biophys. Acta 611: 196 (1980); and J. Med. Chem. 23:240 (1980).

It has been reported that the known complement inhibitors, epsilon-aminocaproic acid and tranexamic acid, have been used with success in the treatment of hereditary angioneurotic edema, a disease state resulting from an inherited deficiency or lack of function of the serum inhibitor of the activated first component of complement (C1 inhibitor), N. Engl. J. Med. 286: 808 (1972); 287: 452 (1972); Ann. Intern. Med. 84: 580 (1976); J. Allergy Clin. Immunol. 60: 38 (1977). Also androgenic steroids have been used successfully in the treatment of this physiological disorder; see Medicine 58: 321 (1979); Arthritis Rheum. 22: 1295 (1979); Am. J. Med. 66: 681 (1979); and J. Allergy Clin. Immunol. 65: 75 (1980).

It has also been reported that the drug pentosanpolysulfoester has an anticomplementary activity on human serum, both in vitro and in vivo, as judged by the reduction in total hemolytic complement activity, Pathol. Biol. 25: 33; 25 (2): 105; 25 (3): 179 (1977).

SUMMARY OF THE INVENTION

It has now been discovered that polysulfonated sennoside A and B derivatives interact with the complement reaction sequence, thereby inhibiting complement activity in body fluids.

This invention also concerns a method of inhibiting the complement system in a body fluid which comprises subjecting body fluid complement to the action of an effective complement inhibiting amount of the above-identified compounds. This invention further deals with a method of inhibiting the complement system in a warm-blooded animal which comprises administering to said animal an effective complement inhibiting amount of the above described compounds.

DETAILED DESCRIPTION OF THE INVENTION

In accordance with the present invention, there are provided novel compounds represented by the following generic formula: ##STR1## wherein R is --SO₃ A; and A is a nontoxic pharmaceutically acceptable salt cation, wherein the salt forming moiety is selected from the group consisting of alkali metal, alkaline earth metal, ammonia and substituted ammonia selected from the group consisting of trialkylamine (C₁ -C₆), piperidine, pyrazine, alkanolamine (C₂ -C₆) and cycloalkylamine (C₃ -C₆) and the compounds may be either the R*,R* or R*,S* isomers.

Specific new compounds of the above formula which are of interest as complement inhibitors include the following: (R*,R*)-5,5'-Bis(β-D-glucopyranosyloxy)-9,9',10,10'-tetrahydro-4,4'-dihydroxy-10,10'-dioxo-[9,9'-bianthracene]-2,2'-dicarboxylic acid, decakis (H-sulfate), decasodium salt [Sennoside A, decakis (H-sulfate), decasodium salt]

(R*,S*)-5,5'-Bis-(β-D-glucopyranosyloxy)-9,9',10,10'-tetrahydro-4,4'-dihydroxy-10,10'-dioxo-[9,9'-bianthracene]-2,2'-dicarboxylic acid, decakis (H-sulfate), decasodium salt [Sennoside B, decakis (H-sulfate), decasodium salt]

This invention further deals with a method of inhibiting the complement system in a body fluid, such as blood serum, which comprises subjecting body fluid complement to the action of an effective complement inhibiting amount of a compound of the above formula. Body fluids can include blood, plasma, serum, synovial fluid, cerebrospinal fluid, or pathological accumulations of fluid such as pleural effusion, etc. This invention also concerns a method of inhibiting the complement system in a warm-blooded animal which comprises administering to said warm-blooded animal an effective complement inhibiting amount of a compound of the above formula.

The above compounds of the present invention find utility as complement inhibitors in body fluids and as such may be used to ameliorate or prevent those pathological reactions requiring the function of complement and in the therapeutic treatment of warm-blooded animals having immunologic diseases such as rheumatoid arthritis, systemic lupus erythematosus, certain kinds of glomerulonephritis, certain kinds of autoallergic hemolytic anemia, certain kinds of platelet disorders and certain kinds of vasculitis. These compounds may also be used in the therapeutic treatment of warm-blooded animals having non-immunologic diseases such as paroxysmal nocturnal hemoglobinurea, hereditary angioneutrotic edema (such as Suramin Sodium, etc.) and inflammatory states induced by the action of bacterial or lysosomal enzymes on the appropriate complement components as, for example, inflammation following coronary occlusion. They may also be useful in the treatment of transplant rejection and ulcers and as blood culture and transport mediums.

The compounds of the present invention may be prepared according to the following flowchart. ##STR2##

In accordance with the above flowchart, commercially available Sennoside A or Sennoside B (1) is suspended in N,N-dimethylacetamide containing triethylamine-sulfur trioxide and heated at 60°-70° C. for 8-24 hours. The reaction is cooled to 5°-10° C. and added to acetone giving a precipitate of (2) where R is SO₃ ⁻.N⁺ H(C₂ H₅)₃. This triethylamine sulfate salt may be converted to the sodium sulfate salt, (2) for example, where R is --SO₃ Na, by a variety of procedures such as conversion through a Dowex® 50W-X8 resin column.

It is generally preferred that the respective product of each process step, described hereinabove, is separated and/or isolated prior to its use as starting material for subsequent steps. Separation and isolation can be effected by any suitable purification procedure such as, for example, evaporation, crystallization, column chromatography, thin-layer chromatography, etc. Also, it should be appreciated that when typical reaction conditions (e.g., temperatures, mole ratios, reaction times) have been given, the conditions which are both avove and below these specified ranges can also be used, though generally less conveniently.

The term "pharmaceutically acceptable salts" refers to those salts of the parent compound which do not significantly or adversely affect the pharmaceutical properties (e.g. toxicity, effectiveness, etc.) of the parent compound. The salt forming moiety of the present invention which are pharmaceutically acceptable include the alkali metals (e.g., sodium, potassium, etc.) alkaline earth metals (e.g., calcium, etc.); ammonia; and substituted ammonia selected from the group consisting of trialkylamine (C₁ -C₆), piperidine, pyrazine, alkanolamine (C₂ -C₆) and cycloalkylamine (C₃ -C₆).

The term "trialkylamine (C₁ -C₆)" defines those amines having three aliphatic fully saturated hydrocarbon substituents containing 1 to 6 carbon atoms either linearly or branched. Typically, these amines are trimethylamine, triethylamine, tripropylamine, dimethylamine, dimethyl-1-propylamine, etc. The term "alkanolamine (C₂ C₆)" refers to the above-defined trialkylamines additionally substituted with at least one and not more than three hydroxy groups on at least two of the alkyl hydrocarbon chains. Such amines are, for example, triethanolamine, tripropanolamine, etc. The term "cyclalkylamine (C₃ -C₆)" is defined as the 3 to 6 fully saturated carbocyclic moieties such as cyclopropyl, methylcyclobutyl, cyclopentyl, cyclohexyl, etc.

As used hereinabove and below unless expressly stated to the contrary, all temperatures and temperature ranges refer to the centigrade system and the terms "ambient" or "room temperature" refer to about 20° C. The term "percent" or "(%)" refers to weight percent and the terms "mole" and "moles" refer to gram moles. The term "equivalent" refers to a quantity of reagent equal in moles to the moles of the preceding or succeeding reactant recited in the Preparation or Example in the term of moles of finite weight or volume.

Whereas the exact scope of the instant invention is set forth in the appended claims, the following specific examples illustrate certain aspects of the present invention. However, the examples are set forth for illustration only and are not to be construed as limitations on the present invention except as set forth in the appended claims.

A further understanding of the invention can be obtained from the following non-limiting Preparations and Examples.

EXAMPLE 1 (R*,R*)-5,5'-Bis-(β-D-glucopyranosyloxy)-9,9',10,10'-tetrahydro-4,4'-dihydroxy-10,10'-dioxo-[9,9'-bianthracene]-2,2'-dicarboxylic acid, decakis (H-sulfate), decasodium salt [Sennoside A, decakis (H-sulfate), decasodium salt]

A suspension of 259 mg of Sennoside A and 1.086 g of triethylamine-sulfur trioxide in 20 ml of dimethylacetamide was shaded from light and heated to 70° C. The temperature was slowly reduced to 60° C. over a period of one hour and then maintained at this temperature for 7 hours. The reaction was cooled to 5°-10° C. and added to 100 ml of acetone. The resulting precipitate was collected by filtration through diatomaceous earth. A 14 g portion of Dowex® 50W-X8 resin (Na⁺ form) was placed in the bottom of a filter flask. The cake was washed with 100 ml of water, catching the filtrate in the flask containing the resin. The resin was then filtered and this filtrate was freeze-dried giving 480 mg of the desired product.

EXAMPLE 2 (R*,S*)-5,5'-Bis-(β-D-glucopyranosyloxy)-9,9',10,10'-tetrahydro-4,4'-dihydroxy-10,10'-dioxo-[9,9'-bianthracene]-2,2'-dicarboxylic acid, decakis (H-sulfate), decasodium salt [Sennoside B, decakis (H-sulfate), decasodium salt]

A 259 mg portion of Sennoside B was reacted as described in Example 1, with the exception that the reaction was heated for 24 hours, giving 671 mg of the desired product.

EXAMPLE 3

    ______________________________________                                         Preparation of Compressed Tablet                                               Ingredient          mg/Tablet                                                  ______________________________________                                         Active Compound     0.5-500                                                    Dibasic Calcium Phosphate NF                                                                       qs                                                         Starch USP          40                                                         Modified Starch     10                                                         Magnesium Stearate USP                                                                             1-5                                                        ______________________________________                                    

EXAMPLE 4

    ______________________________________                                         Preparation of Compressed Tablet - Sustained Action                            Ingredient          mg/Tablet                                                  ______________________________________                                         Active Compound as Aluminum                                                                        0.5-500 (as acid                                           Lake*, Micronized   equivalent)                                                Dibasic Calcium Phosphate NF                                                                       qs                                                         Alginic Acid        20                                                         Starch USP          35                                                         Magnesium Stearate USP                                                                             1-10                                                       ______________________________________                                          *Complement inhibitor plus aluminum sulfate yields aluminum complement         inhibitor. Complement inhibitor content in aluminum lake ranges from           5-30%.                                                                   

EXAMPLE 5

    ______________________________________                                         Preparation of Hard Shell Capsule                                              Ingredient       mg/Capsule                                                    ______________________________________                                         Active Compound  0.05-500                                                      Lactose, Spray Dried                                                                            qs                                                            Magnesium Stearate                                                                              1-10                                                          ______________________________________                                    

EXAMPLE 6

    ______________________________________                                         Preparation of Oral Liquid (Syrup)                                             Ingredient        % W/V                                                        ______________________________________                                         Active Compound   0.05-5                                                       Liquid Sugar      75.0                                                         Methyl Paraben USP                                                                               0.18                                                         Propyl Paraben USP                                                                               0.02                                                         Flavoring Agent   qs                                                           Purified Water qs ad                                                                             100.0                                                        ______________________________________                                    

EXAMPLE 7

    ______________________________________                                         Preparation of Oral Liquid (Elixir)                                            Ingredient        % W/V                                                        ______________________________________                                         Active Compound   0.05-5                                                       Alcohol USP       12.5                                                         Glycerin USP      45.0                                                         Syrup USP         20.0                                                         Flavoring Agent   qs                                                           Purified Water qs ad                                                                             100.0                                                        ______________________________________                                    

EXAMPLE 8

    ______________________________________                                         Preparation of Oral Suspension (Syrup)                                         Ingredient          % W/V                                                      ______________________________________                                         Active Compound as Aluminum                                                                        0.05-5                                                     Lake, Micronized    (acid equivalent)                                          Polysorbate 80 USP  0.1                                                        Magnesium Aluminum Silicate,                                                   Colloidal           0.3                                                        Flavoring Agent     qs                                                         Methyl Paraben USP  0.18                                                       Propyl Paraben USP  0.02                                                       Liquid Sugar        75.0                                                       Purified Water qs ad                                                                               100.0                                                      ______________________________________                                    

EXAMPLE 9

    ______________________________________                                         Preparation of Injectable Solution                                             Ingredient       % W/V                                                         ______________________________________                                         Active Compound  0.05-5                                                        Benzyl Alcohol NF                                                                               0.9                                                           Water for Injection                                                                             100.0                                                         ______________________________________                                    

EXAMPLE 10

    ______________________________________                                         Preparation of Injectable Oil                                                  Ingredient       % W/V                                                         ______________________________________                                         Active Compound  0.05-5                                                        Benzyl Alcohol   1.5                                                           Sesame Oil qs ad 100.0                                                         ______________________________________                                    

EXAMPLE 11

    ______________________________________                                         Preparation of Intra-Articular Product                                         Ingredient               Amount                                                ______________________________________                                         Active Compound          2-20 mg                                               NaCl (physiological saline)                                                                             0-9%                                                  Benzyl Alcohol           0.9%                                                  Sodium Carboxymethylcellulose                                                                           1.5%                                                  pH adjusted to 5.0-7.5                                                         Water for Injection qs ad                                                                               100%                                                  ______________________________________                                    

EXAMPLE 12

    ______________________________________                                         Preparation of Injectable Depo Suspension                                      Ingredient         % W/V                                                       ______________________________________                                         Active Compound    0.05-5                                                                         (acid equivalent)                                           Polysorbate 80 USP 0.2                                                         Polyethylene Glycol 4000 USP                                                                      3.0                                                         Sodium Chloride USP                                                                               0.8                                                         Benzyl Alcohol NF  0.9                                                         HCl to pH 6-8      qs                                                          Water for Injection qs ad                                                                         100.0                                                       Propyl Paraben USP 0.02                                                        Liquid Sugar       75.0                                                        Purified Water qs ad                                                                              100.0                                                       ______________________________________                                    

EXAMPLE 13

    ______________________________________                                         Preparation of Dental Paste                                                    Ingredient           % W/W                                                     ______________________________________                                         Active Compound      0.05-5                                                    Zinc Oxide           15                                                        Polyethylene Glycol 4000 USP                                                                        50                                                        Distilled Water qs   100                                                       ______________________________________                                    

EXAMPLE 14

    ______________________________________                                         Preparation of Dental Ointment                                                 Ingredient         % W/W                                                       ______________________________________                                         Active Compound    0.05-5                                                      Petrolatum, White USP qs                                                                          100                                                         ______________________________________                                    

EXAMPLE 15

    ______________________________________                                         Preparation of Dental Cream                                                    Ingredient          % W/W                                                      ______________________________________                                         Active Compound     0.05-5                                                     Mineral Oil         50                                                         Beeswax             15                                                         Sorbitan Monostearate                                                                              2                                                          Polyoxyethylene 20 Sorbitan                                                    Monostearate        3                                                          Methyl Paraben USP  0.18                                                       Propyl Paraben USP  0.02                                                       Distilled Water qs  100                                                        ______________________________________                                    

EXAMPLE 16

    ______________________________________                                         Preparation of Topical Cream                                                   Ingredient         % W/W                                                       ______________________________________                                         Active Compound    0.05-5                                                      Sodium Lauryl Sulfate                                                                             1                                                           Propylene Glycol   12                                                          Stearyl Alcohol    25                                                          Petrolatum, White USP                                                                             25                                                          Methyl Paraben USP 0.18                                                        Propyl Paraben USP 0.02                                                        Purified Water qs  100                                                         ______________________________________                                    

EXAMPLE 17

    ______________________________________                                         Preparation of Topical Ointment                                                Ingredient         % W/W                                                       ______________________________________                                         Active Compound    0.05-5                                                      Cholesterol        3                                                           Stearyl Alcohol    3                                                           White Wax          8                                                           Petrolatum, White USP qs                                                                          100                                                         ______________________________________                                    

EXAMPLE 18

    ______________________________________                                         Preparation of Spray Lotion (Non-aerosol)                                      Ingredient         % W/W                                                       ______________________________________                                         Active Compound    0.05-5                                                      Isopropyl Myristate                                                                               20                                                          Alcohol (Denatured) qs                                                                            100                                                         ______________________________________                                    

EXAMPLE 19

    ______________________________________                                         Preparation of Buccal Tablet                                                   Ingredient          mg/Tablet                                                  ______________________________________                                         Active Ingredient   3.25                                                       6 × Sugar     290.60                                                     Acacia              14.53                                                      Soluble Starch      14.53                                                      F. D. & C. Yellow No. 6 Dye                                                                        0.49                                                       Magnesium Stearate  1.60                                                                           325.00                                                     ______________________________________                                    

The final tablet will weigh about 325 mg and may be compressed into buccal tablets in flat faced or any other cooling shape convenient for buccal administration.

EXAMPLE 20

    ______________________________________                                         Preparation of Lozenge                                                         Ingredient           g/Lozenge                                                 ______________________________________                                         Active Ingredient    0.0140                                                    Kompact ® Sugar (Sucrest Co.)                                                                   0.7138                                                    6 × Sugar      0.4802                                                    Sorbitol (USP Crystalline)                                                                          0.1038                                                    Flavor               0.0840                                                    Magnesium Stearate   0.0021                                                    Dye                  qs                                                        Stearic Acid         0.0021                                                                         1.4000                                                    ______________________________________                                    

The ingredients are compressed into 5/8" flat based lozenge tooling. Other shapes may also be utilized.

The compounds of the present invention may be administered internally, e.g., orally, intra-articularly or parenterally, to a warm-blooded animal to inhibit complement in the body fluid of the animal, such inhibition being useful in the amelioration or prevention of those reactions dependent upon the function of complement, such as inflammatory process and cell membranes damage induced by antigen-antibody complexes. A range of doses may be employed depending on the mode of administration, the condition being treated and the particular compound being used. For example, for intravenous or subcutaneous use from about 5 to about 50 mg/kg/day, or every six hours for more rapidly excreted salts, may be used. For intra-articular use for large joints such as the knee, from about 2 to about 20 mg/joint per week may be used, with proportionally smaller doses for smaller joints. The dosage range is to be adjusted to provide optimum therapeutic response in the warm-blooded animal being treated. In general, the amount of compound administered can vary over a wide range to provide from about 5 mg/kg to about 100 mg/kg of body weight of animal per day. The usual daily dosage for a 70 kg subject may vary from about 350 mg to about 3.5 g. Unit doses of the acid or salt can contain from about 0.5 mg to about 500 mg.

The compounds of the present invention may also be administered topically in the form of ointments, creams, lotions and the like, suitable for the treatment of complement dependent dermatological disorders.

Moreover, the compounds of the present invention may be administered in the form of dental pastes, ointments, buccal tablets and other compositions suitable for application periodontally for the treatment of periodontitis and related diseases of the oral cavity.

In therapeutic use, the compounds of this invention may be administered in the form of conventional pharmaceutical compositions. Such compositions may be formulated so as to be suitable for oral or parenteral administration. The active ingredient may be combined in admixture with a pharmaceutically acceptable carrier, which carrier may take a wide variety of forms depending on the form of preparation desired for administration, i.e., oral or parenteral. The compounds can be used in compositions such as tablets. Here, the principal active ingredient is mixed with conventional tabletting ingredients such as corn starch, lactose, sucrose, sorbitol, talc, stearic acid, magnesium stearate, dicalcium phosphate, gums, or similar materials as nontoxic pharmaceutically acceptable diluents or carriers. The tablets or pills of the novel compositions can be laminated or otherwise compounded to provide a dosage form affording the advantage of prolonged or delayed action or predetermined successive action of the enclosed medication. For example, the tablet or pill can comprise an inner dosage and an outer dosage component, the latter being in the form of an envelope over the former. The two components can be separated by an enteric layer which serves to resist disintegration in the stomach and permits the inner component to pass intact into the duodenum or to be delayed in release. A variety of materials can be used for such enteric layers or coatings, such materials including a number of polymeric acids or mixtures of polymeric acids with such materials as shellac, shellac and cetyl alcohol, cellulose acetate and the like. A particularly advantageous enteric coating comprises a styrene maleic acid copolymer together with known materials contributing to the enteric properties of the coating. The tablet or pill may be colored through the use of an appropriate nontoxic dye, so as to provide a pleasing appearance.

The liquid forms in which the novel compositions of the present invention may be incorporated for administration include suitable flavored emulsions with edible oils, such as, cottonseed oil, sesame oil, coconut oil, peanut oil, and the like, as well as elixirs and similar pharmaceutical vehicles. Sterile suspensions or solutions can be prepared for parenteral use. Isotonic preparations containing suitable preservatives are also desirable for injection use.

The term "dosage form," as described herein, refers to physically discrete units suitable as unitary dosage for warm-blooded animal subjects, each unit containing a predetermined quantity of active component calculated to produce the desired therapeutic effect in association with the required pharmaceutical diluent, carrier or vehicle. The specification for the novel dosage forms of this invention is indicated by characteristics of the active component and the particular therapeutic effect to be achieved or the limitations inherent in the art of compounding such an active component for therapeutic use in warm-blooded animals as disclosed in this specification. Examples of suitable oral dosage forms in accord with this invention are tablets, capsules, pills, powder packets, granules, wafers, cachets, teaspoonfuls, dropperfuls, ampules, vials, segregated multiples of any of the foregoing and other forms as herein described.

The complement inhibiting activity of the compounds of this invention has been demonstrated by the following identified tests: (i) Test Code 026 (C1 inhibitor)-This test measures the ability of activated human C1 to destroy fluid phase human C2 in the presence of C4 and appropriate dilutions of the test compound. An active inhibitor protects C₂ from C1 and C4; (ii) Test Code 035 (C3-C9 inhibitor)-This test determines the ability of the late components of human complement (C3-C9) to lyse EAC 142 in the presence of appropriate dilutions of the test compound. An active inhibitor protects EAC 142 from lysis by human C3-C9; and (iii) Cap 50 Test-Here, appropriate amounts of the test compound are added to a pool of guinea pig serum in vitro, after which the undiluted serum capillary tube assay of U.S. Pat. No. 3,876,376 is run. The concentration of compound inhibiting 50% is reported. The results of Test Code 026, 035 and Cap 50 appear in Table I showing that the principal compounds of the invention possess highly significant complement inhibiting activity in warm-blooded animals.

                                      TABLE I                                      __________________________________________________________________________     Biological Activities                                                              Compound             026.sup.a                                                                          035.sup.a                                                                          Cap 50                                        __________________________________________________________________________     (R*,R*)-5,5'-Bis-(β-D-glucopyranosyloxy)-9,9',10,-                                                 8.sup.b                                                                            2                                                 10'-tetrahydro-4,4'-dihydroxy-10,10'-dioxo-[9,9'-                              bianthracene]-2,2'-dicarboxylic acid, decakis                                  (H--sulfate) decasodium salt                                                   [Sennoside A, decakis (H--sulfate), decasodium salt]                           (R*,S*)-5,5'-Bis-(β-D-glucopyranosyloxy)-9,9',10,-                                                 7   1   193                                           10'-tetrahydro-4,4'-dihydroxy-10,10'-dioxo-[9,9'-                                                               169                                           bianthracene]-2,2'-dicarboxylic acid, decakis                                  (H--sulfate) decasodium salt                                                   [Sennoside B, decakis (H--sulfate) decasodium salt]                            __________________________________________________________________________      .sup.a Tests identified by code herein.                                        .sup.b Activity in wells, a serial dilution assay: higher well number          indicates higher activity. The serial dilutions are two fold.             

We claim:
 1. A compound selected from those of the formula: ##STR3## wherein R is --SO₃ A; and A is a nontoxic pharmaceutically acceptable salt cation, wherein the salt forming moiety is selected from the group consisting of alkali metal, alkaline earth metal, ammonia and substituted ammonia selected from the group consisting of trialkylamine (C₁ -C₆), piperidine, pyrazine, alkanolamine (C₂ -C₆) and cycloalkylamine (C₃ -C₆); and the compounds may be either the R*,R* or R*,S* isomers.
 2. The compound according to claim 1, (R*,R*)-5,5'-bis(β-D-glucopyranosyloxy)-9,9',10,10'-tetrahydro-4,4'-dihydroxy-10,10'-dioxo-[9,9'-bianthracene]-2,2'-dicarboxylic acid, decakis (H-sulfate), decasodium salt.
 3. The compound according to claim 1, (R*,S*)-5,5'-bis-(β-D-glucopyranosyloxy)-9,9',10,10'-tetrahydro-4,4'-dihydroxy-10,10'-dioxo-[9,9'-bianthracene]-2,2'-dicarboxylic acid, decakis (H-sulfate), decasodium salt.
 4. A method of inhibiting the complement system in a body fluid which comprises subjecting said body fluid to the action of an effective complement inhibiting amount of a compound of the formula of claim
 1. 5. A method of inhibiting the complement system in a warm-blooded animal which comprises administering to said warm-blooded animal an effective complement inhibiting amount of a compound of the formula of claim
 1. 6. The method according to claim 4 or 5, wherein the compound is (R*,R*)-5,5'-bis-(β-D-glucopyranosyloxy)-9,9',10,10'-tetrahydro-4,4'-dihydroxy-10,10'-dioxo-[9,9'-bianthracene]-2,2'-dicarboxylic acid, decakis (H-sulfate), decasodium salt.
 7. The method according to claim 4 or 5, wherein the compound is (R*,S*)-5,5'-bis-(β-D-glucopyranosyloxy)-9,9',10,10'-tetrahydro-4,4'-dihydroxy-10,10'-dioxo[9,9'-bianthracene]-2,2'-dicarboxylic acid, decakis (H-sulfate), decasodium salt.
 8. The method according to claim 5, wherein the compound is administered internally.
 9. The method according to claim 5, wherein the compound is administered topically.
 10. The method according to claim 5, wherein the compound is administered periodontally in the oral cavity.
 11. The method according to claim 5, wherein the compound is administered intra-articularly.
 12. The method according to claim 5, wherein the compound is administered parenterally. 